Henry
Autoexreginated
Archade, what's this NPC's backstory? Peasant Hero? Farmer who turned adventuring? Rogue who settled down farming? Any backstory would spell it out. If there is no backstory, you could select any of these as justified. Farming, unskilled day laboring, all these are good examples of how one would get Commoner levels as opposed to craftsman-type levels. I don't see it as "what class you take", I see it as "what pursuits did you engage in to result in that class?"